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A Chaos Based Blind Digital Image Watermarking in The Wavelet Transform Domain  [PDF]
Jila Ayubi,Shahram Mohanna,Farahnaz Mohanna,Mehdi Rezaei
International Journal of Computer Science Issues , 2011,
Abstract: An effective watermarking algorithm based on the chaotic maps and the discrete wavelet transform for gray scale images is proposed. In the algorithm, the chaotic maps are employed to generate a key space with the length of 1040 numbers to increase the degree of security. Additionally, the XOR operator has been replaced by the mutation process for embedding the images. This improved mutation operator has been used to encrypt the watermark logo. Additionally, the upgraded mapping method determines the location of, DWT, Discrete Wavelet Transform, coefficients where the watermark is embedded. To evaluate the robustness and effectiveness of the proposed method, the effect of several attacks has been simulated on the hidden image. Simulation results indicate that the new algorithm can preserve the hidden information against geometric and non geometric attacks.
Digital Watermarking Technique Based on Wavelet Transform and Spatial Domain
一种基于小波变化和空域的综合数字水印技术

LIU Chang,
刘畅

计算机应用研究 , 2006,
Abstract: A new watermarking scheme by embedding a digital image signature/watermark in the wavelet domain and spatial domain is proposed.The watermark is disparted into two parts.One part is inserted in the low frequency sub-bands of wavelet domain.The other part is inserted in spatial domain directly.There are two steps in the watermark extraction.We can get the original watermark image from the two steps.This method not only has the robustness but also increase the capacity of hiding data.
Image Digital Watermarking Technique Based on Human Visual System and Wavelet Transform Domain
一种基于人眼视觉特性和小波变换域的图像数字水印技术

FU De-sheng,SUN Wen-jing,
傅德胜
,孙文静

计算机科学 , 2008,
Abstract: A digital watermarking algorithm on color image based on human visual system and wavelet transform was proposed.This algorithm adopts YIQ color space to watermark embedding.The three-time random scrambling processing operations were made for the watermark before embedding.Then the wavelet coefficients of Y component were classified making use of the masking peculiarity of visual system.The calculation of JND values and the quantization of wavelet coefficients were made.Finally,the three scrambled watermarki...
Digital Image Watermarking Based on DiscreteWavelet Transform
Digital Image Watermarking Based on Discrete Wavelet Transform

Ding Wei,Yan Weiqi,Qi Dongxu,
丁玮
,闫伟齐,齐东旭

计算机科学技术学报 , 2002,
Abstract: This paper aims at digital watermark which is a new popular research topic recently, presents some methods to embed digital watermark based on modifying frequency coefficients in discrete wavelet transform (DWT) domain. First, the present progress of digital watermark is briefly introduced; after that, starting from Pitas’s method and discarding his pseudo random number method, the authors use a digital image scrambling technology as preprocessing for digital watermarking. Then the authors discuss how to embed a 1-bit digital image as watermark in frequency domain. Finally another digital watermarking method is given in which 3-D DWT is used to transform a given digital image. Based on the experimental results, it is shown that the proposed methods are robust to a large extent. This work is supported by the National Natural Science Foundation of China (Grant No. 60133020) and the NKBRSF Project of China (Grant No. G1998030608). DING Wei received the B.A. and M.A. degrees from Jilin University in 1994 and 1997, and Ph.D. degree from the Institute of Computing Technology, Chinese Academy of Sciences in 2000. He is currently a research fellow in Legend Group Ltd. His research interests include digital image and video processing and compression, computer graphics, information hiding, and digital watermark. YAN Weiqi received the B.A. and M.A. degrees from Xibei University in 1992 and 1994. He is currently a Ph.D. candidate of Institute of Computing Technology, Chinese Academy of Sciences. His research interests include computer graphics and digital image information security. QI Dongxu received the B.A. degree from Jilin University in 1963. He is currently a professor of both Macau University of Science and Technology and North China University of Technology. He is still working as a visiting professor of the Institute of Computing Technology, Chinese Academy of Sciences, Jilin University, Xibei University, Zhongshan University, etc. He serves as an editor of many journals, such as Journal of Computers, Journal of Software, Journal of Image and Graphics, etc. His research interests include computer graphics, computer aided geometry design, numerical analysis, and image processing.
Biorthogonal Wavelet Transform Digital Image Watermarking
B. Rajendra Prasad,k.Vinayaka Kota,B. Mysura Reddy
International Journal of Advanced Computer Research , 2012,
Abstract: With the growing popularity of Digital Mediasthrough the World Wide Web, intellectual propertyneeds copyright protection, prevention of illegalcopying and verification of content integrity. Thenew data hiding techniques need to be developedthat satisfy the requirements of Imperceptibility,Robustness, Capacity, or data hiding rate andSecurity of the hidden data etc. Watermarking hasbeen utilized by researchers for the security ofdigital documents. In this paper we proposed amethod which is an efficient scheme for protectingthe copyrights of digital images with the aid of bothbiometrics and digital watermarking. Newer datahiding techniques that satisfy the requirements ofimperceptibility, robustness, capacities, or datahiding rate and security of the hidden data etc., arebeing developed. Therefore the preference to go fordigital image watermarking, to show resiliencyagainst various unintentional or deliberate attackshas increased. In this paper implementation of twodifferent watermarking algorithms in the frequencydomain will be presented. The first algorithm isbased on the Discrete Wavelet Transform (DWT),the second one is based on the Bi-orthogonalWavelet Transform (BWT). Embedding thewatermark is done by modifying the coefficients ofthe middle frequency band within region of noninterest(RONI) so that the visibility of the imageand diagnosis capability will not be affected and thewatermark will not be removed by attacks. Allschemes are tested using medical images and thesimulation results are compared and thecomparison shows that the best scheme is that basedon using BWT.
Blind digital watermarking algorithm for color image based on integer wavelet transform
基于整型小波变换的彩色图像盲水印算法*

SU Qing-tang,
苏庆堂

计算机应用研究 , 2009,
Abstract: Researched most of the images watermarking methods about gray image embedded into host image at present,this paper proposed a digital watermarking algorithm for color watermark embedded to color host image based on IWT (Integer Wavelet Transform).According to the human visual system peculiarity and quantizing the wavelet coefficient,embedded encrypted watermark adaptively into the Y luminance component of the YCrCb mode in IWT domain.The algorithm allows extracting watermark without the help of original watermark and host image. Experiment results show that the embedded watermark is invisible and robust against common image processing.
An Overview of Transform Domain Robust Digital Image Watermarking Algorithms  [cached]
Baisa L. Gunjal,R.R. Manthalkar
Journal of Emerging Trends in Computing and Information Sciences , 2011,
Abstract: Internet and Multimedia technologies have become our daily needs. Hence it has become a common practice to create copy, transmit and distribute digital data. Obviously, it leads to unauthorized replication problem. Digital image watermarking provides copyright protection to image by hiding appropriate information in original image to declare rightful ownership. Aim of this paper is to provide complete overview of Digital Image watermarking. The study focuses on quality factors essential for good quality watermarking, Performance evaluation metrics (PSNR and Correlation Factors) and possible attacks. Overview of several methods with spatial and Transform Domain watermarking is done with detail mathematical formulae, their implementations, strengths and weaknesses. The generalized algorithms are presented for DWT, CDMA based, DCT-DWT combined approach. The Ridgelet Transform is also introduced. Comparative results of Digital Image Watermarking using LSB, DCT and DWT are also presented. The paper recommends DWT based techniques for achieving Robustness in Digital Image Watermarking.
Digital Watermarking System based on Cascading Haar Wavelet Transform and Discrete Wavelet Transform  [PDF]
Nidal F. Shilbayeh,Adham Alshamary
Journal of Applied Sciences , 2010,
Abstract: The aim of this study was to solve problems of modification, forgery, illegal manipulation and distribution of digital image, especially with the rapid growth of transmission techniques. Although, there are many ways to protect the images, the proposed system suggested a new technique to protect the image for the purposes of ownership, copyright and intellectual property. In this study, we present a new robust and secure hybrid watermarking technique based on Haar Wavelet Transformation (HWT) and Discrete Wavelet Transformation (DWT). The proposed method is constructed by cascading two different but complementary techniques: HWT and DWT wavelet transformations to provide a robust resistance to the protected image against different signal processing attacks. Adding a private key to the watermarking will increase the privacy and security, but by embedding watermark in that private key more protection in wavelet transform will result, leading to more resistant against attacks. The new technique has been proposed to solve the problem of illegal manipulation and distribution of digital image, i.e., HWT and DWT system. Performance evaluation of the proposed method showed improved results in terms of imperceptibility, robustness and security in comparison with others systems.
Lifting Wavelet Transform and Its Application in Digital Watermarking
提升小波变换及其在数字水印中的应用

GAO Shi-wei,GUO Lei,YANG Ning,DU Ya-qin,CHEN Liang,
高世伟
,郭雷,杨宁,杜亚琴,陈亮

计算机应用研究 , 2007,
Abstract: A digital watermarking embedded method based on lifting wavelet transform was presented. Lifting Scheme is a new method to construct biorthogonal wavelet, this method can decrease complexity of count greatly, and reduce runtime effectively. This paper explained the basic principle of lifting scheme in detail, and introduced applications in digital watermarking.
Video Watermarking – Combination of Discrete Wavelet & Cosine Transform to Achieve Extra Robustness  [cached]
Ashish M. Kothari,Ved Vyas Dwivedi
International Journal of Image, Graphics and Signal Processing , 2013,
Abstract: In this paper we worked on the video watermarking technique wherein we took video as a cover medium and some binary images as watermark to be embedded behind the video. Specifically we concentrated on the transform domain technique and we made use of hybridization of the two of the most important and useful transformations, namely Discrete Wavelet Transform and Discrete Cosine Transform, for the purpose of digital watermarking. We evaluated the proposed method with some visual quality matrices and based on the results we concluded that the proposed method provides extra robustness against various attacks as compare to individual use of each transform.
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